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C A Finn

Publications and source records attributed to C A Finn.

At least 19 recordsLinked to original sources

Timing of the window of uterine sensitivity to decidual stimuli in mice.

The refractory period that follows the period of sensitivity to a decidual stimulus in ovariectomized hormone treated mice was investigated. Medroxyprogesterone acetate provided constant progestin concentrations and silastic implants containing oestradiol maintained constant nidatory oestrogen concentrations. The nidatory stimulus was provided by crushing the uterus with a haemostat or by the intrauterine instillation of arachis oil. The decidual response was assessed by measuring changes in uterine weight or by examining the stroma for the presence of alkaline phosphatase. Sensitivity to the oil was first observed approximately 14 h after the insertion of the oestradiol implant but this sensitivity had waned by 32 h and was absent at 40 h. Crushing the uterus initiated a decidual response in mice treated with progestin alone but if the oestradiol implant was inserted then the uterus was responsive to crushing 24 h after insertion but not at 45 h. The traumatic decidual cell reaction (crushing), although not requiring nidatory oestradiol for its successful initiation, was nevertheless subject to the refractoriness that followed oestradiol sensitivity.

Alkaline Phosphatase

Burst fracture of the fifth lumbar vertebra.

Burst fracture of the fifth lumbar vertebra is a rare injury. We report the cases of seven patients who were treated conservatively by immobilization for six to eight weeks in a body-jacket cast that included one lower extremity to the knee. The patients were allowed to walk ten to fourteen days after the injury. A thoracolumbosacral orthosis was worn for an additional three months. No patient had an injury to the sacral root. Two patients had mild lower lumbar motor-root deficits that resolved within one year. All patients had an occasional backache, and two had intermittent radicular-type pain in the distribution of the fifth lumbar or first sacral-nerve root. The degree of compromise of the spinal canal could not be directly related to the degree of neurological deficit; that is, a large compromise of the spinal canal did not necessarily result in a major loss of neurological function. There was no early or late loss of lordosis between the cephalad end-plate of the fourth lumbar vertebra and the cephalad aspect of the sacrum, and there were no signs of progressive collapse of the vertebral body in any patient. In our series, the burst fractures of the fifth lumbar vertebra were stable injuries that caused minimum neurological deficits, and treatment by immobilization in a body-jacket cast was effective.

Adult

Infiltration of neutrophil polymorphonuclear leucocytes into the endometrial stroma at the time of implantation of ova and the initiation of the oil decidual cell reaction in mice.

Polymorphonuclear leucocytes (polymorphs) were found in the endometrial stroma adjacent to implanting blastocysts approximately 100 h after mating. Areas of uterus not containing a blastocyst had very few polymorphs. Ovariectomized mice were treated with hormones to render them sensitive to a decidual stimulus, the intraluminal injection of arachis oil. Areas of uterus responding to the oil (as indicated by the Pontamine Sky Blue reaction) showed an influx of leucocytes into the endometrial stroma between 16 and 36 h after the application of the decidual stimulus. The polymorphs were largely neutrophils. The injection of oil into non-sensitized uteri did not result in polymorph infiltration nor did the injection of physiological saline (which is not deciduogenic) into sensitized uteri. It is concluded that during the early stages of decidualization there is attraction of polymorphs from the blood into the stroma.

Animals

Failure of platelet-activating factor (PAF-acether) to induce decidualization in mice and failure of antagonists of PAF to inhibit implantation.

The possible role of platelet-activating factor (PAF) in the uterine responses associated with implantation was investigated. Attempts to trigger a decidual cell response in the uteri of hormonally sensitized, ovariectomized mice by instilling PAF-acether (1-1000 ng) intraluminally were unsuccessful. The effect of PAF antagonists on implantation was investigated in females ovariectomized on Day 3 of pregnancy and treated with progesterone. Implantation was induced in these females by injection of 10 ng oestradiol-17 beta on Day 8. Hourly intraperitoneal injections of three PAF antagonists (WEB 2086, CV 3988 and BN 52021 at doses of 1.2-1.4 mg/kg) given over a 24-h period starting 1 h before the injection of oestradiol-17 beta had no significant effect on the occurrence of implantation sites. Intraluminal injection of WEB 2086 (15 micrograms) or BN 52021 (5 micrograms) either 3 h before or 6 h after the nidatory oestradiol also had no significant inhibitory effect on implantation. SRI 63-441 given once daily over the first 4 days of pregnancy at a dose of 40 micrograms/30 g body weight had no inhibitory effect on the establishment of pregnancy. These results are not consistent with a critical role for PAF in implantation in mice.

Animals

A study of the early morphological changes initiated in the uterine luminal epithelium by substances (oil and carrageenan) which induce the decidual cell reaction in mice.

Oil, carrageenan or saline were injected into the uteri of ovariectomized mice treated with hormones on schedules which would sensitize, partly sensitize or not sensitize the uterus to an intraluminal decidual stimulus. The uterine epithelium was examined histologically at various times over the succeeding 5 h. Saline did not produce any morphological change whereas almost immediately after the injection of oil or carrageenan epithelial cell death was apparent in the uterus, regardless of hormone treatment. Within 45 min the dead cells had been removed and the epithelium was re-established. Oil droplets were still present in the uterus after 5 h and these were able to stimulate a decidual reaction in partly sensitized animals when oestrogen was administered 18-44 h after the oil instillation, well after the re-establishment of the epithelium. It is suggested that the early transient cell death in the uterine epithelium is not responsible for triggering the decidual reaction but that it is the contact of the oil droplet with an intact epithelium which triggers the response when the hormonal conditions so allow.

Animals

Control of leucocyte infiltration into the decidualized mouse uterus.

Ovariectomized mice were treated with oestrogen and progesterone on a schedule to mimic early pregnancy. Decidualization was induced with oil and uteri were examined at various times after the last progesterone injection. The first morphological change detected in the uterus of decidualized mice following withdrawal of progesterone was infiltration of leucocytes into the stroma. This preceded overt tissue breakdown and extravasation of blood cells, and did not occur following withdrawal of progesterone without decidualization. It is suggested either that there is a release of a chemoattractant from decidual cells before any morphological changes are apparent or that the signal for attracting the leucocytes is released at the time of decidual induction, but that their migration is suppressed by progesterone.

Animals

Varying effects of an IUD on decidualization in mice.

Chronically implanted IUDs consisting of silk suture threads induced decidualization in regions of the uterus remote from the suture site in ovariectomized mice treated with a regimen of progesterone and oestrogen which sensitizes the uterus to a decidual stimulus. In these conditions the IUDs did not inhibit decidualization induced by instilled oil, although they did so in pregnant animals of the same strain. Varying the dose of progesterone and oestrogen did not produce conditions in which IUD's inhibited oil-induced decidualization in ovariectomized mice and progesterone treatment did not prevent IUDs inhibiting decidualization in pregnant animals. However, when ovariectomized mice, sensitized as before, were primed repeatedly with oestrogen to simulate continuing oestrous cycles after IUD insertion, the IUD's inhibited oil-induced decidualization. This involved the premature loss of instilled oil from the uterine lumen and was associated with heavy infiltration of leucocytes into the luminal epithelium. Numbers of leucocytes free in the uterine lumen did not appear to be critical. It appears that contact between the oil and the luminal epithelial surface must be sustained for some length of time to induce a decidual reaction; brief contact is not sufficient to trigger the response.

Animals

Effects of an intra-uterine device on uterine cell division and epithelial morphology in ovariectomized mice treated with oestrogen and progesterone.

Silk threads placed in the uteri of ovariectomized mice increased cell proliferation in all tissues including regions of the uterus remote from the site of insertion. Many of the effects resembled those produced by oestrogens. An intra-uterine device (IUD) increased luminal and glandular mitosis and produced various degrees of luminal epithelial hyperplasia in untreated animals. In progesterone-treated mice bearing IUD's, luminal and stromal mitosis was increased. Epithelial morphology was not affected or luminal mitosis inhibited in oestrogen-treated animals with IUD's, but stromal and glandular mitosis was increased. After combined treatment with progesterone and oestrogen, stromal mitosis was suppressed at the contact site but was increased elsewhere. Both oestrogen and progesterone suppressed the luminal leucocytosis induced by the IUD. Despite this, the IUD prevented complete progestational differentiation of the luminal epithelium and closure of the lumen. The degree to which IUD-induced abnormalities were observed depended on the hormonal status of the animal at the time of sampling.

Animals

Effects of a long-acting progestin on reproductive function in female mice.

The duration of activity of a long-acting progestin, medroxyprogesterone acetate, was compared using three tests for progestational activity: the induction of stromal mitosis in the endometrium, implantation of blastocysts and inhibition of ovulation. The duration of activity was similar in each test and was longer when higher doses were given.

Animals